Tropidurus teyumirim, André Luiz G. Carvalho, 2016

André Luiz G. Carvalho, 2016, Three new species of the Tropidurus spinulosus group (Squamata: Tropiduridae) from Eastern Paraguay, American Museum Novitates 3853, pp. 1-44 : 23-30

Tropidurus teyumirim , n. sp.

Figures 6 A–F, 7A–D

Tropidurus spinulosus guarani —Alvarez et al., 1994: 164. Tropidurus guarani —Frost et al., 1998: 839.

Tropidurus guarani —Frost et al., 2001: 361.

Holotype: MNHNP 12045 (adult male; 26° 2 ′ 59.715 ″ S, 56° 52 ′ 12.809 ″ W, WGS84 system; ~229 m above sea level), collected at the Parque Nacional Ybycui, Paraguarí, Paraguay, by André L. G. de Carvalho, Frederick Bauer, Nicolás Martínez, Viviana Espínola, and Marcelo Dujak in 10 August 2013

Paratypes: AMNH-R 176285 (adult female), MNHNP 11752–53 (two juveniles of undetermined sex), collected with the holotype; AMNH-R 176286 (adult male; 26° 3 ′ 9.529 ″ S, 56° 48 ′ 28.357 ″ W, WGS84 system; 201 m above sea level), AMNH-R 176287 (juvenile female; 26° 3 ′ 6.559 ″ S, 56° 48 ′ 29.570 ″ W, WGS84 system; 205 m above sea level), MNHNP 11754 (juvenile of undetermined sex; 26° 3 ′ 6.48 ″ S, 56° 48 ′ 29.52 ″ W, WGS84 system; 205 m above sea level), collected in Salto Mbocarusu, Parque Nacional Ybycui, Paraguarí, Paraguay, by André L. G. de Carvalho, Frederick Bauer, Nicolás Martínez, Viviana Espínola, Marcelo Dujak, Alejandro Bonzi, and Camila Corvalan in 11 August 2013. MNHNP 4361 (adult male), collected at the Parque Nacional Ybycui, Arroyo Corrientes, Salto Mbocaruzú, Paraguarí, Paraguay, by L. Fitzgerald in 1 May 1981. MNHNP 4383 (adult male), collected at the Parque Nacional Ybycui, Arroyo Corrientes, Salto Mbocaruzú, Paraguarí, Paraguay, by L. Fitzgerald and J. Fillion in 18 April 1981. MNHNP 4386 (adult female) and MNHNP 4388 (adult male) collected at the Parque Nacional Ybycui, Arroyo Corrientes, Salto Mbocaruzú, Paraguarí, Paraguay, by L. Fitzgerald in 23 January 1981. MNHNP 8505 (adult female), MNHNP 8508 (adult male), MNHNP 8509 (adult female), and MNHNP 8510 (adult female) collected at the Parque Nacional Ybycui, Arroyo Corrientes, Saltos Mbocaruzú Paraguarí, Paraguay, by L. Fitzgerald between 17–23 April 1981. MNHNP 8506 (adult female) and MNHNP 8507 (adult male) collected at the Parque Nacional Ybycui, Arroyo Corrientes, 2 km NO de Saltos, Paraguarí, Paraguay, by L. Fitzgerald between 22–23 January 1981.

Morphological diagnosis: Tropidurus teyumirim , n. sp., differs from all congeners by the following combination of characteristics: (1) small-sized adult, reaching 94.41 and 80.79 mm SVL in males and females, respectively; (2) body slightly depressed; (3) large number of vertebral scales (60–83 in males and 79–112 in females); (4) iris golden brown; (5) low vertebral crest in males, reduced in females; (6) one canthal; (7) preocular not contacting canthal; (8) two rows of circumorbitals; (9) reduced tufts of neck spines; (10) sexes not extraordinarily dimorphic in body proportions, scutellation, and color pattern; (11) lips decorated with touches of yellow and intense black vertical bars; (12) ventral head decorated with well-marked black bars oriented lateromedially on chin, connecting posteriorly with a dark medial patch; (13) orange-yellow flash marks on the underside of the thighs and precloacal flap; (14) saxicolous habits.

Comparison with Other Species: Tropidurus teyumirim , n. sp., differs from all other congeners by having smaller size (67.82–94.41 and 61.41–80.79 mm SVL in males and females, respectively). This species is most similar with T. guarani , but differs from the latter by having orange-yellow flash marks on the underside of the thighs and precloacal flap (yellow or creamy yellow in T. guarani ) and higher number of vertebral scales (51–68 in males and 90–98 in females of T. guarani ; 60–83 in males and 79–112 in females of T. teyumirim , n. sp.). Unlike T. lagunablanca , n. sp., T. spinulosus , T. tarara , n. sp., and T. xanthochilus , T. teyumirim , n. sp., exhibits a low vertebral crest (strongly projecting, serrate vertebral crest in the former species), intensely marked black bars on chin, posteriorly reaching a medial dark patch that separates two burnt orange areas on each side of the posterior ventral head, and intensely dark pigmented throat and chest (other patterns in the former species), body slightly depressed (robust body in the former species), and saxicolous habit (former species are arboreal). Tropidurus teyumirim , n. sp., also differ from T. spinulosus and T. xanthochilus in the number of vertebrals (40–56 in males and 55–81 in females of T. spinulosus ; 80–87 in males and 105–118 in females of T. xanthochilus ; 60–83 in males and 79–112 in females of T. teyumirim , n. sp.) and scales around midbody (77–98 in males and 82–95 in females of T. spinulosus ; 94–107 in males and 94–112 in females of T. teyumirim , n. sp.). Tropidurus teyumirim , n. sp., is easily distinguished from T. spinulosus , T. lagunablanca , n. sp., and T. tarara , n. sp., by having orange-yellow flash marks on the underside of thighs and precloacal flap (cream in T. spinulosus and yellow or creamy yellow in T. lagunablanca , n. sp., and T. tarara , n. sp.).

Tropidurus teyumirim , n. sp., is readily distinguished from T. callathelys and T. melanopleurus by having a gray dorsal background and by lacking pronounced sexual dimorphism and dichromatism (males of T. callathelys are dark olive and females have a dark dorsal background and flame scarlet head; males of T. melanopleurus have intense orange head and complex dorsal coloration, with marked black background with light blotches anteriorly, transitioning into a gray background with vivid green-yellow spots, and females have a brown head, black dorsal background laterally decorated with 4–6 red, cream and green bands). Tropidurus teyumirim , n. sp., also differs from T. callathelys and T. melanopleurus by having a low black and white dorsal crest (strongly serrate and distinctly white, contrasting against the dark olive background in T. callathelys ; low and similar in color to background in T. melanopleurus ). Unlike T. callathelys and T. melanopleurus , T. teyumirim , n. sp., has two rows of circumorbital scales (usually one in the former species) and lacks contact between preocular and canthal (preocular and posteriormost canthal in contact in T. callathelys and T. melanopleurus ).

Description of holotype: Small species of Tropidurus , body slightly depressed, SVL 94.41 mm; head subtriangular, length 25% of SVL and width 79% of head length; skull slightly depressed, not particularly elevated at level of orbits; rostrum not particularly shortened relative to other species of the T. spinulosus group; scales of frontonasal region not imbricating posteriorly; one to multiple lenticulate scale organs distributed over the head scales; rostral not remarkably tall, less than twice as high as first supralabial, not tumescent, contacting first supralabials, first lorilabials, and three postrostrals; 1/2 postrostrals; nasal single, not higher than adjacent scales, separated from rostral by postrostral–lorilabial contact; 5/5 enlarged supralabials followed by a series of smaller scales reaching the rictus oris, never contacting subocular; nostril elliptical, occupying about 60% of nasal, positioned posteriorly, directed dorsolaterally, borders elevated; 1/2 canthals; 6/6 enlarged, imbricate, diagonally oriented, laminate superciliaries; 2/2 dorsally keeled preoculars contacting 4/4 loreals; 1/1 dorsally keeled, elongate suboculars medially separated from supralabials by 2 rows of lorilabials; palpebrals granular; 3/3 rows of supraoculars, most scales occupying less than one third, and posteriormost enlarged scales occupying two thirds or less of the width of the supraocular area; 2/2 rows of small, angulate circumorbitals, about the same size of the anterior supraocular scales; 1/1 rows of short, laminate scales separating circumorbitals from enlarged superciliaries, and 1/1 rows of short, laminate scales separating superciliaries from palpebrals; interparietal enlarged, subcordiform, as long as wide; parietal eye visible, positioned medially on the posterior limit of the first third of the interparietal scale; temporals unkeeled, angulate, tumescent, slightly imbricate posteriorly, noticeably larger than lateral neck scales and smaller than parietals; upper temporals slightly larger than lower temporals; parietals angulate; two rows of occipitals separating interparietal from dorsals; ear opening shaped like inverted keyhole, canal deep, largest diameter of meatus about 30% of meatus to snout distance; tympanum semitranslucent; preauricular fringe with a lower cluster of 8/5 spines; mental subtriangular, about 70% of the width of rostral, extending posteriorly to the level of the first third of the adjacent infralabials; 6/5 enlarged infralabials followed by a series of smaller scales reaching the rictus oris; 2/3 enlarged postmentals; 1/1 postmentals in contact with first infralabial; first postmentals not contacting one another; 8/7 sublabials in contact with enlarged infralabials; 78 gulars, slightly imbricate posteriorly; 3/3 nearly evenly spaced tufts of keeled, mucronate spines aligned between the dorsal margin of the ear and dorsal limit of the lateral neck fold, largest spines up to eight times larger than lateral neck spines; clusters of heavily mucronate scales distributed in the area adjacent to the dorsal limit of the antehumeral fold.

Vertebral crest low, serrate, extending to the distal half of the tail; vertebral, spinelike scales larger anteriorly, before nuchal collar; 76 vertebrals; 131 paravertebrals; 101 scales around midbody; 82 ventrals; dorsals large, slightly keeled, mucronate, imbricate, about 20% larger than scales on the flanks; axillary region with diminutive, nonmucronate scales, growing in size and mucronation along the flanks; ventrals slightly smaller than dorsals, smooth, nonmucronate, imbricate; flash marks on underside of the thighs formed by 6/6 rows of glandular scales; 15 cloacal scales, precloacal flap with 8 rows of glandular scales similar to the ones on the underside of the thighs; supracarpals subtriangular, supratarsals subtriangular to subrhomboidal, both smooth and bearing a scale organ on the distal end of the scale; infracarpals smooth and infratarsals mucronate, reducing in size towards digits III and IV; digits thin, cylindrical, slightly compressed; supradigital lamellae smooth, subtriangular to subrhomboidal, scale organ positioned on the distal end of the scales; infradigital lamellae tricarinate, 20/19 under fourth finger, 24 under right fourth toe, left toe amputated, medial keel larger and more projected than lateral keels; ungual similar to subdigital lamellae, nearly smooth; claws long, curved; preaxial scales of brachium moderately keeled and mucronate, postaxial ones with more pronounced keels and mucrons; preaxial thigh scales moderately keeled or smooth, slightly mucronate, postaxial ones heavily keeled and mucronate; 22/21 crus scales, keeled, mucronate; rictal and nuchal folds absent; postauricular and longitudinal neck folds present, antegular fold heavily marked, bearing a deep mite pocket dorsolaterally, coated with diminutive granular scales; supernumerary antegular fold present; oblique neck fold well marked and diverging dorsally; gular fold incomplete medially, extending dorsally to form a heavily marked antehumeral fold internally coated with granular scales; axillary and inguinal folds absent; tail regenerated, cylindrical, slightly compressed; caudal verticils absent; scales of tail up to four times larger than dorsals, keeled, mucronate, imbricate, caudal crest formed by laterally deflected, expanded vertebral scales.

Coloration in life: Pale orange head, dark pigmentation scattered from frontonasal to parietal and temporal regions; two parallel, slightly darker bars oriented perpendicularly to the main body axis distinguishable anteriorly and between the eyes. Orange coloration spread over lateral head and neck. Loreal, lorilabial, palpebral, and circumorbital regions with light gray background. Palpebral, subocular, lorilabial and labial regions decorated with parallel, descending dark bars. Lips light yellow. Iris dark. Dark line, 2–3 scales thick, extends from posterior end of the subocular bar all the way along the lateral neck on each side, passing over the dorsal limit of the lower temporal region, upper auricular region and lateral neck below the base of the tufts of spines. Similar dark line extends from upper temporal region to nuchal collar, flanking the limits of the vertebral region on each side. Mental region with pale background, decorated with dark bars directed antero/lateromedially; a thick dark patch extends medially along the gular region, separating bright orange areas decorated ventrolaterally with light spots 3–7 scales in size on each side of the ventral head.

Vertebral region with pale orange spots 3–12 scales in size, defined against a dark vertebral background. Flanks pale opaline green decorated with numerous green-yellow spots of variable sizes and marked with descending, irregular dark stripes that may anastomose or semireticulate, followed by small dark spots on the lower flanks. The dorsal background is marked with a dorsally complete nuchal collar positioned at the level of gular fold, formed by 3–4 rows of dark scales; dark bar present between parietal region and nuchal collar, preceded by narrower and more elongate subrhomboidal dark mark positioned at the beginning of the dorsal crest. Dark pigmentation covers the throat and extends posteriorly into the chest and base of forearms. Ventral ground coloration pale orange, area just posterior to forelimbs scattered with irregular bright orange spots, ventrolaterally positioned; straight, three scales thick, bright orange stripe extends from axillary to inguinal region. Brachium pale opaline green with irregular dark spots or stripes proximally, grading into pale orange background with well-marked, nearly parallel stripes distally. Background of thighs is a mix of pale opaline green and pale orange coloration scattered with irregular dark stripes and spots not as marked and symmetrical as the ones on forelimbs. Dorsum of manus and pes pale orange, marked with well-defined dark stripes, including digits. Ventral surface of limbs pale orange. Femoral and precloacal flash marks orange-yellow, 20/21 and 16 scales long, respectively. Tail with coloration similar to dorsum, laterally decorated with greenyellow spots similar to those on the flanks, ventral side pale orange, ventrolateral straight, bright orange line, similar to, but discontinuous with orange stripes on lateral limits of venter.

Coloration in preservative: Orange pigmentation on dorsal head and neck faded into dull cream coloration. Dorsal body gained an overall darker appearance, opaline green coloration turned grayish, offering more contrast for numerous light green spots spread over the dorsum, flanks, and tail, specially the larger ones distributed throughout the vertebral region. Dark marks and irregular spots preserved on vertebral region, dorsum, and flanks. Greenyellow spots that brightly colored the flanks of the specimen in life were completely washed out. Coloration of mental region preserved, with a series of dark stripes directed antero/lateromedially. Dark medial patch on the ventral side of the head well marked, extending throughout the throat. Light spots of variable sizes scattered posteriorly on the ventrolateral area of the head. Nuchal collar, throat, and chest dark coloration remained nearly unchanged. Ventral coloration faded, bright orange stripes along the lateral limits of the venter almost entirely faded. Dark stripes preserved on the dorsal face of limbs, manus, and pes, pale orange background coloration almost completely lost in both fore- and hind limbs. Flash marks of the precloacal flap and underside of the thighs turned yellow, not preserving the originally intense orange-yellow coloration. Tail preserved coloration similar to dorsum, but green-yellow spots originally present laterally were washed out; ventral coloration became pale cream and bright orange ventrolateral stripes were lost.

Measurements of the holotype (in mm): SVL: 94.41; TL: 79.33 (tail regrown); BH: 11.34; BW: 27.69; HH: 10.64; EOS: 21.29; HL: 23.90; HW: 18.89; AL: 14.70; FAL: 12.45; HDL: 16.71; THL: 19.20; SL: 16.48; FOL: 24.94; AGD: 40.37.

Etymology: The specific epithet, teyumirim , is a newly coined, indeclinable word derived from the juxtaposition of the noun teyu (= “lizard”) and the adjective mirim (= “little”), literally meaning “little lizard,” in Guarani language. The name alludes to the reduced size of T. teyumirim , n. sp., the smallest species of the T. spinulosus species group known to date.

Distribution, natural history, and conservation status: Tropidurus teyumirim , n. sp., is known only from the type locality, in the western side of the Parque Nacional Ybycui, and a couple of sites approximately 6.5 km east of the type locality, inside the same park (Salto Mbocarusu and area near the confluence of the rivers Karaimi and Corrientes) (figs. 1, 7E–H). The Serranía de Ybycui comprises the entire distribution of the species as currently known. The geography of the region is similar to that of the areas occupied by T. guarani , marked by the presence of exposed sedimentary rock terraces on mountaintops surrounded by semideciduous Atlantic Forest. However, T. teyumirim , n. sp., also dwells on the margins of the main rivers inside the Parque Nacional Ybycui. In riverine areas, the species uses large sedimentary rocks exposed on riverbanks and near waterfalls (saltos). The number of specimens collected by different workers at the Parque Nacional Ybycui within the past three decades indicates that the population of T. teyumirim , n. sp., is large in that area. Daytime temperatures during my visit to the Parque Nacional Ybycui in early August 2013, varied 6°–13° C; hence, the few active specimens of T. teyumirim , n. sp., observed are unlikely to represent the actual density of the new species in the type locality. Since a formal assessment of the distribution limits, ecological requirements, and population size of T. teyumirim , n. sp., is currently unavailable, I recommend the new species to be classified as “data deficient” according to the rules proposed by IUCN (2001).

Tropidurus teyumirim , n. sp., is diurnal, heliophilous, and saxicolous, hardly differing from T. guarani with respect to its ecology. It uses the same types of sedimentary rocks as its congener and has similar coloration pattern, which provides camouflage against the lichenous background. Nothing is known about the dietary preferences of T. teyumirim , n. sp. Tropidurus teyumirim , n. sp., uses rock surfaces for basking and seeks shelter underneath rock blocks and in rock crevices. Lizards can be found lying dormant underneath rock blocks early in the morning when temperatures are still low. The species was never observed on three trunks along the limits or inside the forests surrounding the exposed sedimentary terraces. Tropidurus teyumirim , n. sp., is syntopic with Notomabuya frenata (Cope, 1862) and an undescribed species of the genus Ameivula at the Parque Nacional Ybycui, however, aspects of their interactions are unknown.

Figures

FIGURE 6. Holotype of Tropidurus teyumirim, n. sp. (MNHNP 12045). A – C. Dorsal, lateral, and ventral views of the head. D – F. Dorsal, lateral, and ventral views of the body.